Add ObjectValidators.LanguageCode type

Signed-off-by: marcin mikołajczak <git@mkljczk.pl>

lib/pleroma/ecto_type/activity_pub/object_validators/language_code.ex

@@ -0,0 +1,25 @@
+# Pleroma: A lightweight social networking server
+# Copyright © 2017-2023 Pleroma Authors <https://pleroma.social/>
+# SPDX-License-Identifier: AGPL-3.0-only
+
+defmodule Pleroma.EctoType.ActivityPub.ObjectValidators.LanguageCode do
+  use Ecto.Type
+
+  import Pleroma.Web.CommonAPI.Utils, only: [is_good_locale_code?: 1]
+
+  def type, do: :string
+
+  def cast(language) when is_binary(language) do
+    if is_good_locale_code?(language) do
+      {:ok, language}
+    else
+      {:error, :invalid_language}
+    end
+  end
+
+  def cast(_), do: :error
+
+  def dump(data), do: {:ok, data}
+
+  def load(data), do: {:ok, data}
+end

lib/pleroma/web/activity_pub/object_validators/common_fields.ex

@@ -57,7 +57,7 @@ defmodule Pleroma.Web.ActivityPub.ObjectValidators.CommonFields do
       field(:replies_count, :integer, default: 0)
       field(:like_count, :integer, default: 0)
       field(:announcement_count, :integer, default: 0)
-      field(:language, :string)
+      field(:language, ObjectValidators.LanguageCode)
       field(:inReplyTo, ObjectValidators.ObjectID)
       field(:url, ObjectValidators.BareUri)